Police said it was not a case of custodial death.
Shaheer (48), was taken into custody from Cheranelloor area yesterday for allegedly stabbing another person, police said.
He was allegedly found in a highly inebriated and physically weak condition and taken for medical examination in the presence of locals soon after he was taken into custody.
A case under various IPC sections dealing with murder attempt was registered against him after he was taken to the Cheranelloor police station, police said.
Shaheer, lodged in the station cell last night, was allegedly found in an unconscious state this morning.He was immediately taken to the government hospital here but died before reaching the hospital, police said.
Opposition leader Ramesh Chennithala demanded a high-level probe into the incident.
Chennithala, also a former Home Minister, alleged that such custodial deaths have been occurring in the state ever since CPI(M)-led LDF government assumed power.